1. Field of the Invention
The present invention relates to a shutter device of a camera for carrying out a soft focus photography.
2. Description Related to the Prior Art
In a market is sold a cheap camera, in which a photo film can be changed and a focus mechanism and an exposure mechanism are omitted. Further, as a type of the cheap camera, a lens-fitted photo film unit is widely known, which includes a simple photographic mechanism and in which the filmstrip is previously loaded in producing process. The lens-fitted photo film unit can be used only once, and when a user thereof provides it to a photofinisher without removing the filmstrip, he can obtain a processed filmstrip and photo prints.
Such a sort of the camera has a simple structure to be produced in a low cost. For example, a fixed focus type of a taking lens is used, which is constructed of one or two lens elements, and a hitting type of the shutter device is used. In the hitting type, a swingable shutter blade is hit by a release lever, and thereafter swung back by bias of a spring.
As a method of portrait photography, there is a soft focus photograph. When a soft focus photograph is designated with use of a normal camera, a filter for the soft focus photography is provided in front of a taking lens of the normal camera. By making the soft focus photograph, a small part of an incident light into the taking lens irregularly reflects to form a portrait image whose outlines of objects are reproduced in a suitably smaller sharpness.
In the normal camera in which the focusing can be made, outlines in the image are adequately softened with the filter for the soft focus photography.
However, an inexpensive camera includes a taking lens of a fixed focus, which is likely to form a certain image out of focus. If the soft focus filter is combined with the fixed-focus camera, an out-of-focus image may be recorded also with softened portions at smaller sharpness, to result in an unacceptable photograph. If good image quality is intended at a low cost, no soft focus photography is available.
An object of the present invention is to provide a shutter device of a camera for soft focus photography, in which a fixed focus type of a taking lens is loaded.
In order to achieve the objects and other object of the present invention, in a shutter device of the present invention that is loaded in a camera, a shutter drive member is swung from a primary position to an end position in response with photographing operation. In accordance with the swing of the shutter drive member, a shutter blade moves between a closed position, a small stop position and an open position. In the closed position, the shutter blade entirely closes a shutter opening formed in a camera body of the camera. In the small stop position, a part of the shutter opening is exposed. In the open position, the shutter opening is entirely exposed. The shutter drive member is biased toward the closed position by a spring. The shutter drive member and the shutter blade are connected by a transmission member. Interlocking with the moving of the shutter drive member to the end position, the transmission member moves the shutter blade from the closed position to the small stop position, and further moves the shutter blade after setting to the small stop position for a predetermined time, so as to make the shutter opening entirely appear. Then, interlocking with the moving of the shutter drive member to the closed position by bias of the spring, the transmission member keeps the shutter blade in the small stop position for the predetermined time, and thereafter moves the shutter blade to the closed position, to cover the shutter opening with the shutter blade.
The camera in which the shutter device of the present invention is loaded includes a flash device for emitting a flashlight and a sync switch for the flash device. In order to drive the sync switch, the shutter drive member has a switch depressing portion. While the shutter blade is set to the small stop position for the predetermined time, the shutter drive member swings and thereby the switch depressing portion presses the sync switch. Thus the sync switch is turned ON.
The shutter blade is constructed of two rotatable blade members having a same rotary shaft, for rotating in directions opposite to one another. While the blade members rotate, the shutter opening gradually appears or is covered. Further, the transmission member is rotatable. An end of the transmission member has an end cam groove in which a cam pin of the shutter drive member is fitted, and another end of the transmission member has an end guide pin and is fitted in a guide groove formed in each of the blade members. In accordance with the swing of the transmission member, the end guide pin moves in the guide groove such that the blade members rotate oppositely to each other. Thus the swing of the shutter drive member is transmitted to the blade members.
According to the shutter device of the present invention, the stop having the predetermined size is temporarily kept in opening and closing the shutter blades. In the camera including the shutter device, an image with core formed through the small stop and a slightly softened image formed through the shutter opening are synthesized on the photo film. Accordingly, the soft focus photography adequate for the portrait photography can be carried out.
Further, in the camera, while the small stop having the predetermined size is formed, the flashlight is emitted. Accordingly, a sharp image formed through the small stop, and a slightly softened image formed through the entirely exposed shutter opening are synthesized on the photo film. Therefore, the soft focus photography adequate for the portrait photograph can be made.